This quest to discover XEP-0403 (Mediated Information eXchange (MIX): Presence Support.) was automagically added, to fulfill the quest at Discover XEPs. As of 2018-11-03 the status of this Standards Track XEP is Experimental. What does that even mean?! Check it out at XEP-0403: Mediated Information eXchange (MIX): Presence Support. 